Downregulation of KLK13 promotes the invasiveness and metastasis of oesophageal squamous cell carcinoma.

KLK13 downregulation occurs in tumour tissues in comparison with adjacent normal tissues from patients with oesophageal squamous cell carcinoma (OSCC). KLK13 mRNA levels were tested in OSCC tumour tissues and adjacent noncancerous tissues from 138 patients. In addition, the correlation between KLK13 mRNA levels and OSCC clinicopathologic features was analysed. KLK13 mRNA levels decreased notably in tumour tissues compared with those in adjacent noncancerous tissues. And decreased KLK13 mRNA levels indicated significant correlations with higher tumour grade, elevated TNM (UICC, 2009) stage classification, deeper infiltration and more lymph node metastases. And thus KLK13 may be a promising diagnostic marker. Decreased KLK13 mRNA levels also correlate with poor survival, which indicates that KLK13 mRNA expression may be a potential prognostic marker, although it could not be an independent prognostic factor by multivariate analysis. In vitro experiments of the OSCC cell lines KYSE150 and KYSE450 demonstrated that overexpression of KLK13 inhibits cell invasion and migration. Thus, KLK13 is a unique novel molecule useful for monitoring OSCC progression. Full elucidation of the role of KLK13 in OSCC may reveal avenues for investigating the molecule's functional potential as a novel therapeutic drug for targeting OSCC.